Uncontrolled Memory Allocation in Netty - CVE-2026-45416

Vulnerability identifier: #VU133450

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-45416

CWE-ID: CWE-789

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to uncontrolled memory allocation in SslClientHelloHandler.decode() when processing a TLS ClientHello that does not fit in the first record. A remote attacker can send a specially crafted ClientHello with a large handshake length to cause a denial of service.

The issue is exposed by the commonly used SniHandler and AbstractSniHandler constructors because they disable the client hello length guard and do not schedule a handshake timeout.

Netty
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Package Hub 15
Development Tools Module
Netezza Appliance
DevOps Deploy
webMethods developer portal
webMethods ControlPlane
IBM SPSS Analytic Server
IBM Watson Discovery for IBM Cloud Pak for Data
Jira Service Management Data Center
IBM Sterling B2B Integrator
Crowd Data Center
IBM Sterling Connect:Direct Web Services
UCD - IBM UrbanCode Deploy
IBM Maximo Application Suite - Manage Component
Jira Software Data Center
Bamboo Data Center
IBM Sterling File Gateway
IBM App Connect for Manufacturing
netty-tcnative
netty-tcnative-debugsource
netty-javadoc
netty
Red Hat Camel for Spring Boot
JBoss Data Grid

Install security update from vendor's website.

Netty - addressed in versions 4.1.135, 4.2.15
Netezza Appliance - update to 1.0.2.0
IBM Watson Discovery for IBM Cloud Pak for Data - update to 5.3.3
Jira Service Management Data Center - addressed in versions 10.3.24, 11.3.8
IBM Sterling B2B Integrator - addressed in versions 6.2.1.2.1, 6.2.2.1.1
IBM Sterling File Gateway - addressed in versions 6.2.1.2.1, 6.2.2.1.1
Crowd Data Center - update to 7.2.2
IBM Sterling Connect:Direct Web Services - addressed in versions 6.3.0.20, 6.4.0.9
UCD - IBM UrbanCode Deploy - addressed in versions 7.2.3.25, 7.3.2.20
DevOps Deploy - addressed in versions 8.1.2.8, 8.2.2.1
IBM Maximo Application Suite - Manage Component - addressed in versions 9.0.28, 9.1.20, 9.2.1
Jira Software Data Center - addressed in versions 9.12.38, 10.3.24, 11.3.8
Bamboo Data Center - addressed in versions 10.2.21, 12.1.9
webMethods developer portal - update to 11.1 Fix14
webMethods ControlPlane - update to 11.1 Fix11
netty-tcnative - update to 2.0.79-150200.3.45.1
netty-tcnative-debugsource - update to 2.0.79-150200.3.45.1
netty-javadoc - update to 4.1.135-150200.4.50.1
netty - update to 4.1.135-150200.4.50.1
Red Hat Camel for Spring Boot - update to 4.18
JBoss Data Grid - update to 8.6.2

• https://github.com/netty/netty/security/advisories/GHSA-x4gw-5cx5-pgmh

• Multiple vulnerabilities in Netty
• Multiple vulnerabilities in IBM SPSS Analytic Server
• IBM Watson Discovery Cartridge update for Netty
• SUSE update for netty, netty-tcnative
• IBM DevOps Deploy / IBM UrbanCode Deploy (UCD) update for Netty
• IBM Sterling Connect:Direct Web Services update for Netty
• Multiple vulnerabilities in Bamboo Data Center
• IBM Maximo Application Suite - Manage Component update for Netty
• Multiple vulnerabilities in IBM App Connect for Manufacturing
• Multiple vulnerabilities in Red Hat Camel for Spring Boot 4
• Multiple vulnerabilities in JBoss Data Grid 8.6
• Multiple vulnerabilities in Crowd Data Center
• Multiple vulnerabilities in Jira Service Management Data Center
• Multiple vulnerabilities in Jira Software Data Center
• IBM Netezza Appliance update for Netty
• Multiple vulnerabilities in IBM webMethods API Management
• Multiple vulnerabilities in IBM Sterling B2B Integrator and IBM Sterling File Gateway